7.3.14 Dial Test Indicator Flashcards
What is a dial test indicator (DTI)?
A high-precision measurement tool with an accuracy of 0.01 mm or 0.001” used to measure the alignment of shafts or check the smoothness of surfaces.
What are the two types of dial test indicators?
Plunger DTI and Lever DTI.
What does a typical plunger type DTI consist of?
A graduated dial, a needle driven by a clockwork mechanism, a smaller embedded clock face, and a spring-loaded plunger.
What is the measurement range of dial indicators?
Typically from 0.25 mm to 300 mm (0.015 in to 12.0 in) with graduations of 0.001 mm to 0.01 mm or 0.00005 in to 0.001 in.
How does a lever type DTI operate?
The probe swings in an arc around its hinge point, measuring the deflection of the arm.
What materials are commonly used for contact points of lever arms?
Steel, tungsten carbide, ruby, Teflon, or PVC.
What is the purpose of Go/No-go gauges?
To quickly determine whether parts are within specified limits without adjusting the gauge for each reading.
What do the two sets of jaws in Go/No-go gauges represent?
One set is slightly over the required size (go size) and the other is slightly under the required size (no-go size).
What does it indicate if a part enters the first gap of a Go/No-go gauge?
The part is oversized.
What does it indicate if a part passes both gaps of a Go/No-go gauge?
The part is undersized.
What is a typical application for Go/No-go gauges?
Checking control cable terminal fittings after swaging.
